The Savarez 500AJ Classical Guitar Strings are part of the Corum Alliance series, featuring Savarez Corum basses paired with Alliance carbon fiber composite trebles. Corum basses offer a very flexible feel while retaining a quick response and high dynamic range. Alliance trebles are similar to gut strings, with very long life and smooth feel, which reduces left hand noise. The 500AJ set is comprised of high tension Alliance trebles and Corum basses.